1. Field of the Invention
The present invention relates to an image-comparing apparatus and an image-comparing method, each for comparing compressed and encoded images with a specific image to determine whether they are identical or similar to the specific image. The invention also relates to an image-retrieving apparatus and an image-retrieving method, each for retrieving images substantially identical to a specific image, from compressed and encoded video contents.
2. Description of the Related Art
A technique of retrieving images substantially identical to a specific image, from unknown video contents, by using the specific image as retrieval query, has been demanded for the purpose of retrieving images from, for example, video contents. Jpn. Pat. Appln. Laid-Open Publication No. 2004-45565, for example, proposes the technique of extracting the characteristic amount of each frame from the video contents within a short time, generating a characteristic vector for the frame. The characteristic vector of each fame is compared with the characteristic vector of a specific image. Thus, images substantially identical to the specific image are retrieved from the video contents.